Editorial Type:
Article
Article Type:
Research Article

Numerical Study on Flow Pass of a Three-Dimensional Obstacle under a Strong Stratification Condition

W. Sha Department of Mechanical Engineering, Nagoya Institute of Technology, Nagoya, Japan

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K. Nakabayashi Department of Mechanical Engineering, Nagoya Institute of Technology, Nagoya, Japan

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H. Ueda Research Institute for Applied Mechanics, Kyushu University, Kyushu, Japan

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Print Publication:
01 Oct 1998
DOI:
https://doi.org/10.1175/1520-0450(1998)037<1047:NSOFPO>2.0.CO;2
Page(s):
1047–1054
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Abstract

A three-dimensional, nonhydrostatic, numerical turbulent model was used to study the flow pass of a three-dimensional obstacle under a strong stratification condition. The numerical results clarify the behavior of the flow at a low Froude number, showing the relative importance of the stratification effects on the flow splitting, wave breaking, and lee vortices phenomena.

A vertical vorticity budget study shows that the tilting and friction terms are important to the formation of the lee vortices. On the other hand, the advection and stretching terms are responsible for carrying the vorticity to the lee side. The baroclinicity term can be ignored.

Corresponding author address: W. Sha, Department of Mechanical Engineering, Nagoya Institute of Technology, Gokiso-Cho, Showaku, Nagoya 466, Japan.

Abstract

A three-dimensional, nonhydrostatic, numerical turbulent model was used to study the flow pass of a three-dimensional obstacle under a strong stratification condition. The numerical results clarify the behavior of the flow at a low Froude number, showing the relative importance of the stratification effects on the flow splitting, wave breaking, and lee vortices phenomena.

A vertical vorticity budget study shows that the tilting and friction terms are important to the formation of the lee vortices. On the other hand, the advection and stretching terms are responsible for carrying the vorticity to the lee side. The baroclinicity term can be ignored.

Corresponding author address: W. Sha, Department of Mechanical Engineering, Nagoya Institute of Technology, Gokiso-Cho, Showaku, Nagoya 466, Japan.

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